Image processing apparatus, image processing method, and program

ABSTRACT

An image processing apparatus according to the present invention includes an image forming unit configured to form an image, a measuring unit configured to measure the formed image, a control unit configured to control execution of a single-color calibration to be performed to correct reproduction characteristics of a single-color formed by the image forming unit based on a measuring result of a single-color image formed with a single-color recording agent and execution of a multi-color calibration to be performed to correct reproduction characteristics of a multi-color image formed by the image forming unit based on a measuring result of a multi-color formed with a plurality of recording agents, and a selection unit configured to select whether to cause the control unit to perform the multi-color calibration after completing the single-color calibration or cause the control unit to perform any one of the single-color calibration and the multi-color calibration.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation, and claims the benefit, of U.S.patent application Ser. No. 15/364,065, presently pending and filed onNov. 29, 2016, which is a continuation, and claims the benefit, of priorU.S. patent application Ser. No. 13/937,427, filed on Jul. 9, 2013 andissued as U.S. Pat. No. 9,542,629 on Jan. 10, 2017, and claims thebenefit of, and priority to, Japanese Patent Application No.2012-155530, filed Jul. 11, 2012, which applications are herebyincorporated by reference herein in their entireties.

FIELD OF THE INVENTION

The present invention relates to an image processing apparatus and animage processing method that can correct a color of an image to beoutput from a printer, and a program for generating image processingparameters.

DESCRIPTION OF THE RELATED ART

The recent improvement in performance of electrophotographic apparatusescan realize high image quality comparable to that of a printing machine.However, the instability of each electrophotographic apparatus, which ispeculiar thereto, tends to cause a color variation that is larger thanthat of a printing machine.

In general, a “single-color” calibration technique is conventionallyinstalled in an electrophotographic apparatus. The “single-color”calibration technique includes generating a look-up table (LUT) usableto correct one-dimensional gradation characteristics corresponding toeach of cyan, magenta, yellow, and black (hereinafter, simply referredto as C, M, Y, and K) toners. The LUT is a table that indicates outputdata corresponding to respective input data segmented at specificintervals. Using the LUT is useful in expressing nonlinearcharacteristics to which no calculation formula is applicable. Further,the “single-color” is a color that is reproducible using a single tonerof C, M, Y, or K. Performing the single-color calibration is useful tocorrect single-color reproduction characteristics, such as a maximumdensity and a gradation.

As discussed in Japanese Patent Application Laid-Open No. 2011-254350, a“multi-color” calibration technique using a four-dimensional LUT isconventionally proposed. The “multi-color” is a composite color that isreproducible using a plurality of toners of red, green, and blue or gray(based on CMY). Especially, according to the electrophotography, evenwhen a one-dimensional LUT is used to correct single-color gradationcharacteristics, a nonlinear difference tends to occur if a plurality oftoners is used to express a “multi-color.” Performing the multi-colorcalibration in such a case is useful to correct multi-color reproductioncharacteristics which can be expressed by a combination (e.g., asuperposition) of a plurality of color toners.

A processing procedure of the calibration including a “multi-color”calibration is described below. First, patches are printed on arecording medium, such as a sheet of paper, based on single-color chartdata that is usable to perform the “single-color” calibration. Then, theprinted patches are read by a scanner or a sensor. The read patch datais compared with target values having been set beforehand, and aone-dimensional LUT is generated which is used to correct differencesbetween read patch data and the target values. Then, patches are printedon a recording medium based on multi-color chart data that reflects theobtained one-dimensional LUT to perform the “multi-color” calibration,and the printed patches are read by the scanner or the sensor. Further,the read patch data is compared with target values having been setbeforehand, and a four-dimensional LUT is generated which is used tocorrect differences between read patch data and the target values.

As described above, it is feasible to realize highly accurate correctionby performing the “multi-color” calibration in such a way as to correctmulti-color characteristics that cannot be corrected by the“single-color” calibration.

In addition, it is desirable to start the processing from the“single-color” calibration and then perform the “multi-color”calibration, as described above. However, a significantly longprocessing time is required to complete both the single-colorcalibration and the multi-color calibration. For example, in a case of auser who frequently performs single-color printing, there is a higherpossibility of performing the single-color calibration because the“multi-color” print is not performed so often. In addition, in anelectrophotographic apparatus, there is a tendency that a nonlineardifference occurs in a case of “multi-color” processing as compared witha case of “single-color” processing. Therefore, “multi-color”characteristics may not be sufficiently corrected even in a case where“single-color” characteristics are sufficiently corrected. Accordingly,in a case of a user who frequently performs “multi-color” (e.g.,photograph) printing, there is a higher possibility of performing themulti-color calibration rather than performing the single-colorcalibration.

In response to above-described users' demands, there is a mechanismwhich provides two buttons independently to enable a user to select eachof the single-color calibration and the multi-color calibration andindependently perform the selected calibration (see Fuji Xerox technicalreport NO. 19 2010).

However, according to the above-described technique discussed in FujiXerox technical report NO. 19 2010, the single-color calibration and themulti-color calibration are processing to be independently performed.Therefore, if only one of two calibrations is chiefly performed (toooften), there is a possibility that the correction accuracy of thecalibration may deteriorate.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, an image processingapparatus includes an image forming unit configured to form an image, ameasuring unit configured to measure an image formed by the imageforming unit, a control unit configured to control execution of asingle-color calibration to be performed to correct reproductioncharacteristics of a single-color formed by the image forming unit basedon a measuring result obtained in a case where the measuring unitmeasures a single-color image formed with a single-color recording agentby the image forming unit, and execution of a multi-color calibration tobe performed to correct reproduction characteristics of a multi-colorformed by the image forming unit based on a measuring result obtained ina case where the measuring unit measures a multi-color image formed witha plurality of recording agents by the image forming unit, and aselection unit configured to select whether to cause the control unit toperform the multi-color calibration after completing the single-colorcalibration or cause the control unit to perform any one of thesingle-color calibration and the multi-color calibration.

According to the present invention, an image processing apparatuscapable of selectively performing a single-color calibration or amulti-color calibration can prevent the correction accuracy in thecalibration from deteriorating which is caused by that only one of twocalibrations is chiefly performed (too often).

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a configuration of an image processing system.

FIG. 2 is a flowchart illustrating an example procedure of imageprocessing.

FIG. 3 is a flowchart illustrating an example procedure of single-colorcalibration processing.

FIG. 4 is a flowchart illustrating an example procedure of multi-colorcalibration processing.

FIGS. 5A to 5C illustrate a plurality of charts that can be used in thesingle-color calibration and the multi-color calibration.

FIG. 6 illustrates an example of a menu screen for executing thesingle-color calibration and/or the multi-color calibration.

FIG. 7 is a flowchart illustrating an example procedure of themulti-color calibration processing according to a first exemplaryembodiment.

FIG. 8 illustrates an example of a user interface (UI) screen accordingto the first exemplary embodiment.

FIG. 9 is a flowchart illustrating an example procedure of thesingle-color calibration processing according to a second exemplaryembodiment.

FIG. 10 illustrates an example of a UI screen according to the secondexemplary embodiment.

FIG. 11 is a flowchart illustrating an example procedure of calibrationprocessing according to a third exemplary embodiment.

FIG. 12 illustrates an example of a UI screen according to the thirdexemplary embodiment.

FIG. 13 is a flowchart illustrating an example procedure of calibrationprocessing according to a fourth exemplary embodiment.

FIGS. 14A and 14B illustrate examples of UI screens according to thefourth exemplary embodiment.

DESCRIPTION OF THE EMBODIMENTS

A first exemplary embodiment of the present invention is describedbelow. According to the present exemplary embodiment, when thecalibration is to be performed, a user can select whether to performboth a single-color calibration and a multi-color calibration or toperform one of them. Therefore, the calibration can be performedappropriately considering a usage condition of the user.

Further, according to the present exemplary embodiment, since both ofthe single-color calibration and the multi-color calibration areperiodically performed, it can prevent the correction accuracy in thecalibration from deteriorating.

FIG. 1 illustrates a configuration of an image processing systemaccording to the present exemplary embodiment. A multi function printer(MFP) 101 is an image processing apparatus that forms images using cyan,magenta, yellow, and black (hereinafter, C, M, Y, and K) toners. The MFP101 is connected to other network devices via a network 123. A personalcomputer (PC) 124 is connected to the MFP 101 via the network 123. ThePC 124 includes a printer driver 125 that transmits print data to theMFP 101.

The MFP 101 is described in detail below. A network interface (I/F) 122can receive print data. A controller 102 includes a central processingunit (CPU) 103, a renderer 112, and an image processing unit 114. TheCPU 103 includes an interpreter 104 that can interpret a pagedescription language (PDL) portion included in the received print dataand generate intermediate language data 105.

A color management system (CMS) 106 can perform color conversion using asource profile 107 and a destination profile 108, and can generateintermediate language data (post CMS) 111. Profile information usable inthe color conversion to be performed by the CMS 106 is described below.The source profile 107 is used to convert a device-dependent colorspace, e.g., RGB and CMYK color spaces, into a device-independent colorspace, e.g., L*a*b* (hereinafter, referred to as “Lab”) and XYZ colorspaces. Lab is the color space specified by the CIE (CommissionInternationale de l'Eclairage=International Commission on Illumination).XYZ is also a device-independent color space that is similar to Lab,which can express a color with three types of stimulus values. Thedestination profile 108 is used to convert a device-independent colorspace into a device (e.g., printer 115) dependent CMYK color space.

On the other hand, another color management system (CMS) 109 can performcolor conversion using a device link profile 110 and can generateintermediate language data (post CMS) 111. The device link profile 110is used to directly convert a device-dependent color space (e.g., RGB orCMYK) into the device (e.g., the printer 115) dependent CMYK colorspace. Selection of the CMS 106 or the CMS 109 is determined accordingto a setting by the printer driver 125.

According to the present exemplary embodiment, a plurality of colormanagement systems (106 and 109) is provided according to the type ofeach profile (107, 108, or 110). However, a single CMS can be configuredto process a plurality of types of profiles. Further, the type of eachprofile is not limited to the examples described according to thepresent exemplary embodiment. Any type of profile can be used if it canuse the device-dependent CMYK color space of the printer 115.

The renderer 112 can generate a raster image 113 based on the generatedintermediate language data (post CMS) 111. The image processing unit 114can perform image processing on the raster image 113 or an image read bya scanner 119. The image processing unit 114 is described in detailbelow.

The printer 115 which is connected to the controller 102 is a printercapable of forming an image on a sheet using C, M, Y, and K color tonersbased on output data. The printer 115 includes a paper feeding unit 116that can feed paper as a recording material, a paper discharge unit 117that can discharge the paper on which an image is formed, and ameasuring unit 126.

The measuring unit 126 includes a sensor 127 that can obtain a spectralreflectance value and a device-independent color space (e.g., Lab orXYZ) value. The printer 115 includes a CPU 129 that can control variousoperations to be performed by the printer 115. The CPU 129 can controlthe measuring unit 126. The measuring unit 126 reads a patch from arecording medium (e.g., paper) printed by the printer 115 with thesensor 127. The measuring unit 126 transmits numerical informationobtained from the patch to the controller 102. The controller 102performs calculations using the numerical information received from themeasuring unit 126. The controller 102 utilizes the calculation resultfor performing the single-color calibration or the multi-colorcalibration.

The MFP 101 includes a display device 118 which is operable as a userinterface (UI) for displaying an instruction message to a user or anoperational state of the MFP 101. The display device 118 can be used inthe single-color calibration or the multi-color calibration.

The scanner 119 includes an auto document feeder. The scanner 119irradiates image (s) on a bundle of documents or a sheet of a documentwith light emitted from a light source (not illustrated) and cause alens to form a reflected document image on a solid-state image sensor,such as a charge coupled device (CCD) sensor. Then, the scanner 119obtains a raster image reading signal, as image data, from thesolid-state image sensor.

The MFP 101 includes an input device 120 that is operable as aninterface that receives instructions input by a user. The input devicemay be partly configured as a touch panel and integrated with thedisplay device 118.

The MFP 101 includes a storage device 121 that stores data processed bythe controller 102 and data received from the controller 102.

A measuring device 128 is an external measuring device that is connectedto a network or to the PC 124. Similar to the measuring unit 126, themeasuring device 128 can obtain a spectral reflectance value and adevice-independent color space (e.g., Lab or XYZ) value.

Next, an example of processing to be performed by the image processingunit 114 is described with reference to FIG. 2. FIG. 2 is a flowchartillustrating an example of image processing applied to the raster image113 or an image read by the scanner 119. An Application SpecificIntegrated Circuit (ASIC) (not illustrated) included in the imageprocessing unit 114 executes the processing illustrated in FIG. 2.

In step S201, the image processing unit 114 receives image data. Then,in step S202, the image processing unit 114 determines whether thereceived data is scanning data received by the scanner 119 or the rasterimage 113 received from the printer driver 125.

If the received data is not the scanning data (NO in step S202), thereceived data is the raster image 113 having been bitmap rasterized bythe renderer 112. The raster image 113 becomes a CMYK image 211 which isconverted into printer device-dependent CMYK by the CMS.

If the received data is the scanning data (YES in step S202), thereceived data is an RGB image 203. Therefore, in step S204, the imageprocessing unit 114 performs color conversion processing to generate acommon RGB image 205. The common RGB image 205 is an image defined in adevice-independent RGB color space and can be converted into adevice-independent color space (e.g., Lab) through calculations.

On the other hand, in step S206, the image processing unit 114 performscharacter determination processing to generate character determinationdata 207. According to the present exemplary embodiment, the imageprocessing unit 114 detects an edge of the image or the like to generatethe character determination data 207.

Next, in step S208, the image processing unit 114 performs filterprocessing on the common RGB image 205 using the character determinationdata 207. According to the present exemplary embodiment, the imageprocessing unit 114 differentiates the filter processing applied to acharacter portion and the filter processing applied to the remainingportion.

Next, in step S209, the image processing unit 114 performs backgroundcolor removal processing. In step S210, the image processing unit 114performs color conversion processing to generate the CMYK image 211 fromwhich the background has been removed.

Next, in step S212, the image processing unit 114 performs multi-colorcorrection processing using a four-dimensional look up table (4D-LUT)217. The 4D-LUT is usable to convert a combination of C, M, Y, and Ksignal values into a combination of different C, M, Y, and K signalvalues in outputting respective toners. The 4D-LUT 217 can be generatedby the “multi-color calibration” described below. Thus, it becomesfeasible to correct a “multi-color”, i.e., a composite color obtainableusing a plurality of toners, with reference to the 4D-LUT.

If the multi-color correction processing in step S212 is completed, thenin step S213, the image processing unit 114 corrects single-colorgradation characteristics of respective C, M, Y, and K colors, using aone-dimensional look up table (1D-LUT) 218. The 1D-LUT is usable tocorrect each of the C, M, Y, and K colors (i.e., single-colors). The1D-LUT 218 can be generated by the “single-color calibration” describedbelow.

Finally, in step S214, the image processing unit 114 performs halftoneprocessing (e.g., screen processing, error diffusion processing, or thelike) to generate a CMYK image (binary value) 215. Then, in step S216,the image processing unit 114 transmits the processed image data to theprinter 115.

An example of the “single-color calibration” for correcting single-colorgradation characteristics to be output from the printer 115 is describedwith reference to FIG. 3. Performing the single-color calibration isuseful to correct single-color color reproduction characteristics (e.g.,maximum density characteristics and gradation characteristics). Thecolor reproduction characteristics corresponding to the respective C, M,Y, and K toners used by the printer 115 can be corrected together whenthe calibration is performed. More specifically, the processing in theflowchart illustrated in FIG. 3 can be performed simultaneously for therespective C, M, Y, and K colors.

FIG. 3 is the flowchart illustrating a processing procedure forgenerating the 1D-LUT 218 to be used to correct the single-colorgradation characteristics. The CPU 103 performs the processing in theflowchart illustrated in FIG. 3. The storage device 121 stores thegenerated 1D-LUT 218. The display device 118 displays a UI screenincluding an instruction message to a user. The input device 120receives an instruction from the user.

In step S301, the CPU 103 obtains chart data “A” 302 stored in thestorage device 121. The chart data “A” 302 is used to correct themaximum density of each single color. The chart data “A” 302 includessignal values (e.g., 255) based on which maximum density data ofrespective C, M, Y, and K “single-colors” can be obtained.

Next, in step S303, the CPU 103 causes the image processing unit 114 toperform image processing on the chart data “A” 302, and causes theprinter 115 to print a chart “A” 304. FIG. 5A illustrates an example ofa chart 501 printed based on the chart data “A” 302. The chart 501includes four patches 502, 503, 504, and 505 of the respective C, M, Y,and K colors which have been printed at their maximum densities. In thiscase, the image processing unit 114 performs only the halftoneprocessing in step S214. The image processing unit 114 does not performthe 1D-LUT correction processing in step S213 and does not perform the4D-LUT correction processing in step S212.

Next, in step S305, the CPU 103 measures the density of the printedproduct of the chart “A” 304 with the scanner 119 or the sensor 127provided in the measuring unit 126, and obtains a measurement value “A”306. The measurement value “A” 306 indicates a density value of each ofthe C, M, Y, and K colors. Next, in step S307, the CPU 103 corrects themaximum density of the measurement value “A” 306 of each color withreference to the measurement value “A” 306 and a target value “A” 308 ofthe maximum density value having been set beforehand. According to thepresent exemplary embodiment, the CPU 103 adjusts device setting values,such as laser output and development bias, of the printer 115 so as toequalize the maximum density with the target value “A” 308.

Next, in step S309, the CPU 103 obtains chart data “B” 310 stored in thestorage device 121. The chart data “B” 310 includes signal values of“single-color” gradation data of C, M, Y, and K. A chart “B” 312including patches printed on a recording medium based on the chart data“B” 310 is illustrated in FIG. 5B. A chart 506 illustrated in FIG. 5B isan example of a printed product of the chart “B” 312 including aplurality of patches printed on a recording medium based on the chartdata “B” 310. The chart 506 illustrated in FIG. 5B includes four patchgroups 507, 508, 509, and 510 each including a plurality of gradationdata of C, M, Y, and K colors, respectively.

Next, in step S311, the CPU 103 causes the image processing unit 114 toperform image processing on the chart data “B” 310. The CPU 103 causesthe printer 115 to print the chart “B” 312. In this case, the imageprocessing unit 114 performs only the halftone processing in step S214.The image processing unit 114 does not perform the 1D-LUT correctionprocessing in step S213 and does not perform the 4D-LUT correctionprocessing in step S212. The printer 115 is already subjected to themaximum density correction in step S307. Therefore, in this state, theprinter 115 can perform printing at the maximum density which issubstantially equal to the target value “A” 308.

Next, in step S313, the CPU 103 performs measurement with the scanner119 or the sensor 127, and obtains a measurement value “B” 314. Themeasurement value “B” 314 indicates a density value that is obtainablefrom the gradation of each of C, M, Y, and K colors. Then, in step S315,the CPU 103 generates the 1D-LUT 218 to be used to correct thesingle-color gradation characteristics based on the measurement value“B” 314 and a target value “B” 316 having been set beforehand.

Next, an example of the “multi-color calibration” for correctingmulti-color characteristics to be output from the printer 115 isdescribed with reference to FIG. 4. Performing the multi-colorcalibration is useful to correct multi-color reproductioncharacteristics which can be expressed using a combination (orsuperposition) of a plurality of color toners. The CPU 103 provided inthe controller 102 can perform the following processing. The storagedevice 121 stores the obtained 4D-LUT 217. Further, the display device118 displays a UI screen including an instruction message to a user, andthe input device 120 receives an instruction from the user.

The multi-color calibration is performed for correcting a multi-color tobe output from the printer 115 after execution of the single-colorcalibration. Accordingly, it is desirable to perform the multi-colorcalibration immediately after completing the single-color calibration.

In step S401, the CPU 103 obtains information about “multi-color” chartdata “C” 402 stored in the storage device 121. The chart data “C” 402 isused to correct the multi-color and includes signal values of the“multi-color” that is a combination of C, M, Y, and K colors. A chart“C” 404 including a plurality of patches printed on a recording mediumbased on the chart data “C” 402 is illustrated in FIG. 5C. FIG. 5Cillustrates an example of a chart 511 printed based on the chart data“C” 402. A patch 512 and other patches included in the chart 511 is amulti-color patch configured as a combination of C, M, Y, and K colors.

Next, in step S403, the CPU 103 causes the image processing unit 114 toperform image processing on the chart data “C” 402 and causes theprinter 115 to print the chart “C” 404. In the multi-color calibration,since the multi-color characteristics of the device is corrected aftercompleting the single-color calibration, the image processing unit 114performs image processing using the 1D-LUT 218 generated in thesingle-color calibration.

Next, in step S405, the CPU 103 measures a multi-color of the printedproduct of the chart “C” 404 by the scanner 119 or the sensor 127provided in the measuring unit 126, and obtains a measurement value “C”406. The measurement value “C” 406 indicates multi-color characteristicsof the printer 115 after completion of the single-color calibration.Further, the measurement value “C” 406 is defined in adevice-independent color space. According to the present exemplaryembodiment, the measurement value “C” 406 is a Lab value. If the scanner119 is used in the measurement, the CPU 103 converts an obtained RGBvalue into a Lab value using a three-dimensional (3D)-LUT (notillustrated).

Next, in step S407, the CPU 103 obtains a Lab→CMY 3D-LUT 409 stored inthe storage device 121 and generates a Lab→CMY 3D-LUT (corrected) 410 byreflecting a difference between the measurement value “C” 406 and atarget value “C” 408 having been set beforehand in the obtained Lab→CMY3D-LUT 409. The Lab→CMY 3D-LUT is a three-dimensional LUT usable tooutput a CMY value that corresponds to an input Lab value.

As one specific example of generation methods, the CPU 103 adds adifference between the measurement value “C” 406 and the target value“C” 408 to an input-side Lab value of the Lab→CMY 3D-LUT 409 andperforms interpolation calculation on the difference reflected Lab valueusing the Lab→CMY 3D-LUT 409. As a result, the CPU 103 can generate theLab→CMY 3D-LUT (corrected) 410.

Next, in step S411, the CPU 103 obtains a CMY→Lab 3D-LUT 412 stored inthe storage device 121 and performs calculations using the Lab→CMY3D-LUT (corrected) 410. Accordingly, the CPU 103 generates a CMYK→CMYK4D-LUT 217. The CMY→Lab 3D-LUT is a three-dimensional LUT usable tooutput a Lab value that corresponds to an input CMY value.

A method for generating the CMYK→CMYK 4D-LUT 217 is specificallydescribed below. The CPU 103 generates a CMY→CMY 3D-LUT based on theCMY→Lab 3D-LUT 412 and the Lab→CMY 3D-LUT (corrected) 410. Next, the CPU103 generates the CMYK→CMYK 4D-LUT 217 in such a way as to equalize aninput value of K with an output value of K. The CMY→CMY 3D-LUT is athree-dimensional LUT usable to output a corrected CMY value thatcorresponds to an input CMY value.

FIG. 6 illustrates an example of a UI screen 601 that enables a user toselect the single-color calibration and/or the multi-color calibration.The display device 118 can display the UI screen 601 illustrated in FIG.6. A button 602 is used for receiving an input of starting thesingle-color calibration. A button 603 is used for receiving an input ofstarting the multi-color calibration. A button 604 is used for receivingan input of performing the multi-color calibration after completing thesingle-color calibration.

In a case where the button 604 is selected, the CPU 103 starts thesingle-color calibration, and after completing the single-colorcalibration, starts the multi-color calibration.

More specifically, after completing the single-color calibration, theCPU 103 starts the multi-color calibration with printing the multi-colorcalibration chart “C” 404. Alternatively, the CPU 103 may cause thedisplay device 118 to display a UI screen including a button forstarting the multi-color calibration and start the multi-colorcalibration if the button is pressed by the user.

On the other hand, in a case where the button 602 is selected, the CPU103 performs only the single-color calibration. Similarly, in the casewhere the button 603 is selected, the CPU 103 performs only themulti-color calibration.

The reason why the single-color calibration button and the multi-colorcalibration button are separately provided is described below. The CPU103 refers to the 1D-LUT 218 generated in the single-color calibrationin printing the chart “C” 404 to be used in the multi-color calibration.Accordingly, it is desirable to perform the multi-color calibration tocorrect multi-color reproduction characteristics immediately after thesingle-color calibration has been completed, in other words, immediatelyafter single-color reproduction characteristics have been corrected.However, if the CPU 103 performs both of two types of calibrations, arelatively long processing time is required for a user to complete thecalibrations.

Accordingly, to reduce the processing time, the CPU 103 enables a userto select the single-color calibration or the multi-color calibrationconsidering a usage environment. Thus, the frequency of performing eachcalibration may be variable. For example, if a user often performsmonochrome printing, the frequency of performing the multi-colorcalibration decreases. On the other hand, if a user often performsmulti-color printing (e.g., photograph printing), the frequency ofperforming the multi-color calibration increases.

In addition, it is useful to limit a timing when a user can select adesired button on the color correction menu on the UI screen 601.

In general, the power source of an image processing apparatus is turnedoff in the night and turned on in the morning. Therefore, it is usefulto permit a user to select only the button 604 in response to turning onthe power source of the MFP 101. Alternatively, it is useful to permit auser to select only the button 604 if both of the calibrations have notbeen performed within a predetermined time. Alternatively, it is usefulto permit a user to select only the button 604 if both of thecalibrations have not been performed until a predetermined number ofsheets are used in printing.

Further, the single-color calibration and the multi-color calibrationcan be automatically performed in series if a predetermined time haselapsed, a predetermined number of sheets are used in printing, or thepower source is turned on.

As described above, the system is configured to permit a user to selectonly the button 604 at a predetermined timing when the user performs thecalibration and to prompt a user to select the multi-color calibrationimmediately after completing the single-color calibration atpredetermined intervals.

As described above, a user can select whether to perform the multi-colorcalibration after completing the single-color calibration (namely,perform both of the calibrations) or perform either the single-colorcalibration or the multi-color calibration. Accordingly, the calibrationcan be performed appropriately considering a usage condition of theuser.

Further, the system can perform control to permit a user to selectperforming both calibrations at predetermined time intervals and preventthe correction accuracy of reproduction characteristics in thecalibration from deteriorating due to non-execution of one of twocalibrations.

Next, an operation to be performed when the button 603 is pressed toselect the multi-color calibration is described below. When the button603 for performing only the multi-color calibration is pressed, the CPU103 causes the display device 118 to display a UI screen that requests auser to determine whether to perform the single-color calibration beforestarting the multi-color calibration. Such a UI screen display is usefulin preventing the correction accuracy in the multi-color calibrationfrom deteriorating due to non-execution of the single-color calibration.FIG. 7 is a flowchart illustrating an example procedure of calibrationprocessing to be performed when the multi-color calibration is selected.The CPU 103 provided in the controller 102 performs the followingprocessing illustrated in FIG. 7. The storage device 121 stores theobtained data. Further, the display device 118 displays a UI screenincluding an instruction message to a user, and the input device 120receives an instruction from the user.

In step S701, the CPU 103 starts the multi-color calibration. Morespecifically, the multi-color calibration is started when a user pressesthe button 603 displayed by the display device 118 via the input device120.

Next, in step S702, the CPU 103 displays a UI screen that requests auser to determine whether to perform the single-color calibration. FIG.8 illustrates an example of a UI screen 801 that can be displayed by thedisplay device 118. The UI screen 801 includes a message field 802 inwhich a message for prompting a user to determine whether to perform thesingle-color calibration on condition that single-color reproductioncharacteristics are appropriate in performing the multi-colorcalibration (on condition that the single-color calibration has beenperformed) is displayed. The UI screen 801 includes two buttons 803 and804 that enable the user to determine whether to perform thesingle-color calibration in advance. If the “YES” button 803 isselected, the CPU 103 performs the single-color calibration. If the “NO”button 804 is selected, the CPU 103 does not perform the single-colorcalibration.

The UI screen 801 may be displayed every time when the multi-colorcalibration is selected and before the multi-color calibration isperformed. Alternatively, the UI screen 801 may be displayed only whenthe number of multi-color calibrations performed after the lastsingle-color calibration exceeds a threshold value. For example, inperforming the calibration, the UI screen 801 may be displayed when themulti-color calibrations are consecutively performed five times.

In step S703, the CPU 103 determines whether to perform the single-colorcalibration in advance. More specifically, the CPU 103 determineswhether the user has selected either the button 803 or the button 804 onthe UI screen 801.

If it is determined that the single-color calibration is not performed(NO in step S703), then in step S704, the CPU 103 performs themulti-color calibration. The processing to be performed in step S704 issimilar to the processing performed in steps S401 to S411, and thereforeredundant description thereof will be avoided.

If it is determined that the single-color calibration is performed (YESin step S703), then in step S705, the CPU 103 performs the single-colorcalibration. Subsequently, in step S704, the CPU 103 performs themulti-color calibration. The processing to be performed in step S705 issimilar to the processing performed in steps S301 to S315, and thereforeredundant description thereof will be avoided.

In the processing of the flowchart illustrated in FIG. 7, the CPU 103constantly performs the multi-color calibration after completing thesingle-color calibration. However, it is useful to enable a user todetermine whether to perform the multi-color calibration aftercompleting the single-color calibration.

Through the above-described processing of the flowchart illustrated inFIG. 7, the system can request a user to determine whether to performthe single-color calibration before starting the multi-colorcalibration. Thus, the correction accuracy in the multi-colorcalibration can be prevented from deteriorating due to non-execution ofthe single-color calibration.

Next, an operation to be performed when the button 602 is pressed toselect the single-color calibration is described below. If a userpresses the button 602 for performing only the single-color calibration,the CPU 103 causes the display device 118 to display a UI screen thatrequests a user to determine whether to perform the multi-colorcalibration after completing the single-color calibration. Such a UIscreen display is useful in preventing the correction accuracy in thecalibration from deteriorating due to non-execution of the multi-colorcalibration.

As described above, the system performs processing for requesting a userto determine whether to perform the single-color calibration ifperforming only the multi-color calibration is instructed.

In the above-described processing, as a result of the request, the usermay continuously deny to perform the multi-color calibration each timewhen the single-color calibration is completed. In this case, the usermay continue use of the printer which cannot attain the expectedaccuracy.

Considering the above-described situation, the system performsprocessing illustrated in FIG. 9, which includes displaying a UI screenthat requests a user to determine whether to perform the multi-colorcalibration after completing the single-color calibration.

The CPU 103 provided in the controller 102 performs the processing ofthe flowchart illustrated in FIG. 9. The storage device 121 stores theobtained data. Further, the display device 118 displays a UI screenincluding an instruction message to a user, and the input device 120receives an instruction from the user.

First, in step S901, the CPU 103 performs the single-color calibration.

More specifically, the CPU 103 starts the single-color calibration whena user presses the button 602 displayed by the display device 118 viathe input device 120.

The processing to be performed in step S901 is similar to the processingperformed in steps S301 to S315, and therefore redundant descriptionthereof will be avoided.

Next, in step S902, the CPU 103 causes the display device 118 to displaya UI screen that requests a user to determine whether to perform themulti-color calibration. FIG. 10 illustrates an example of a UI screen1001 that can be displayed by the display device 118. The UI screen 1001includes a message field 1002 in which a message for recommending a userto perform the multi-color calibration after completing the single-colorcalibration is displayed. The UI screen 1001 includes two buttons 1003and 1004 that enable the user to determine whether to perform themulti-color calibration. If the “YES” button 1003 is selected, the CPU103 performs the multi-color calibration. If the “NO” button 1004 isselected, the CPU 103 does not perform the multi-color calibration.

The UI screen 1001 may be displayed every time when the single-colorcalibration is selected. Alternatively, the UI screen 1001 may bedisplayed only when the number of single-color calibrations performedafter the last multi-color calibration exceeds a threshold value. Forexample, in performing the calibration, the UI screen 1001 may bedisplayed when the single-color calibrations are consecutively performedfive times.

In step S903, the CPU 103 determines whether to perform the multi-colorcalibration. More specifically, the CPU 103 determines whether theselected button is the “YES” button 1003 or the “NO” button 1004.

If it is determined that the multi-color calibration is not performed(NO in step S903), the CPU 103 terminates the processing of theflowchart illustrated in FIG. 9.

If it is determined that the multi-color calibration is performed (YESin step S903), then in step S904, the CPU 103 performs the multi-colorcalibration. The processing to be performed step S904 is similar to theprocessing performed in steps S401 to S411, and therefore redundantdescription thereof will be avoided.

Through the above-described processing of the flowchart illustrated inFIG. 9, the system can request a user to determine whether to performthe multi-color calibration after completing the single-colorcalibration among two types of the calibrations. Therefore, the systemcan prevent the multi-color calibration from being kept unperformedafter completing the single-color calibration. Thus, the system canprevent a user from continuously using the printer without obtaining thecorrection accuracy to be expected in the calibration.

According to the processing procedure described in the first exemplaryembodiment, when a user selects one of two calibrations, the CPU 103requests the user to determine whether to perform the other calibration.

However, a long processing time is required when two types ofcalibrations are performed constantly and continuously as a result ofthe request. In addition, when the printer usage status that is variabledepending on each user is taken into consideration, a sufficientcorrection result may be obtained in some cases even when only one ofthe two types of calibrations is performed. For example, in general, amulti-color is easily variable, compared to a single-color. Therefore,if a user frequently generates multi-color data, such as photographdata, performing the multi-color calibration at a higher frequencycompared to that of the single-color calibration may be effective toobtain a sufficient correction result. In this case, a user candetermine the execution frequency of the calibration based on user'sexperience in such a way as to perform the single-color calibration onceafter continuously performing the multi-color calibration five times.

Accordingly, in a second exemplary embodiment, if a user issues aninstruction to perform the multi-color calibration, the system displaysthe number of multi-color calibrations performed after the lastsingle-color calibration when requesting the user to determine whetherto perform the single-color calibration before performing themulti-color calibration.

FIG. 11 illustrates a processing procedure according to the presentexemplary embodiment. The CPU 103 provided in the controller 102performs the following processing illustrated in FIG. 11. The storagedevice 121 stores the obtained data. Further, the display device 118displays a UI screen including an instruction message to a user, and theinput device 120 receives an instruction from the user.

In step S1101, the CPU 103 starts the multi-color calibration.

More specifically, the CPU 103 starts the multi-color calibration if auser presses the button 603 displayed by the display device 118 via theinput device 120.

Next, in step S1102, the CPU 103 reads a multi-color calibrationexecution counter 1103 and displays a UI screen that displays the numberof multi-color calibrations having been performed after the lastsingle-color calibration. The multi-color calibration execution counter1103 stores the number of multi-color calibrations having been performedafter the last single-color calibration.

Next, in step S1104, the CPU 103 displays a UI screen that requests auser to determine whether to perform the single-color calibration. FIG.12 illustrates an example of a UI screen 1201 that can be displayed bythe display device 118. The UI screen 1201 includes a message field 1202and two buttons 1203 and 1204 that are similar to the field 802 and thebuttons 803 and 804 illustrated in FIG. 8 and therefore redundantdescription thereof will be avoided. The UI screen 1201 includes amessage field 1205 that indicates the number of multi-color calibrationshaving been performed after the last single-color calibration. A userwho frequently performs the multi-color calibration can check the numberof multi-color calibrations and determine whether to perform thesingle-color calibration before starting the multi-color calibration.

In step S1105, the CPU 103 determines whether to perform thesingle-color calibration in advance. More specifically, the CPU 103determines whether either the button 1203 or the button 1204 has beenselected.

If it is determined that the single-color calibration is performedbefore starting the multi-color calibration (YES in step S1105), then instep S1106, the CPU 103 performs the single-color calibration. Theprocessing to be performed in step S1106 is similar to the processingperformed in steps S301 to S315, and therefore redundant descriptionthereof will be avoided.

Next, in step S1107, the CPU 103 initializes the multi-color calibrationexecution counter 1103. In the initialized state, the number ofmulti-color calibrations performed after the single-color calibration iszero.

On the other hand, if it is determined that the single-color calibrationis not performed before starting the multi-color calibration (NO in stepS1105), or after completing the initialization of the multi-colorcalibration execution counter, then in step S1108, the CPU 103 performsthe multi-color calibration. The processing to be performed in stepS1108 is similar to the processing performed in steps S401 to S411, andtherefore redundant description thereof will be avoided.

In step S1109, the CPU 103 adds the number of executions to themulti-color calibration execution counter 1103. Then, the CPU 103terminates the processing of the flowchart illustrated in FIG. 11. Morespecifically, as the multi-color calibration has been performed once,the multi-color calibration execution counter 1103 increments its countvalue by one.

According to the present exemplary embodiment, the number of multi-colorcalibrations having been performed is displayed in the message field1205 of the UI screen 1201. Alternatively, it is useful to provide athreshold value beforehand with respect to the number of executions andswitch the message contents to be displayed based on a thresholddetermination result. How to switch the message contents is specificallydescribed below. For example, if it is determined beforehand by a userto perform the single-color calibration after the multi-colorcalibration has been consecutively performed five times, a thresholdvalue to be set for the number of performed multi-color calibrations isfive. In this case, the system does not display a message forrecommending the single-color calibration if the number of performedmulti-color calibrations is equal to or less than four. However, if thenumber of performed multi-color calibrations has reached five, thesystem displays a message for recommending the single-color calibration.The UI contents may be shifted to a screen that informs a user offorcibly starting the single-color calibration when the number ofperformed multi-color calibrations has reached the threshold value, inaddition to the display of the above-described message.

Further, according to the present exemplary embodiment, the systemdisplays the number of multi-color calibrations having been performedafter the last single-color calibration. However, any other informationcan be displayed as long as the information is helpful for a user todetermine whether to perform the single-color calibration. For example,it is useful to display date and time when the single-color calibrationwas performed last time and the present date and time to enable a userto determine whether to perform the single-color calibration.

According to the above-described exemplary embodiment, the system canrequest a user to determine whether to perform a single-colorcalibration before starting a multi-color calibration among two types ofthe calibrations. Thus, the system can prevent the correction accuracyin the multi-color calibration from deteriorating due to non-executionof the single-color calibration.

Further, displaying the number of multi-color calibrations having beenperformed after the last single-color calibration enables a user toeasily determine whether to perform a single-color calibration beforestarting a multi-color calibration.

Next, a third exemplary embodiment in which the number of color printedsheets is compared with the number of monochrome printed sheets, and aUI screen is switched according to a monochrome printing output ratio isdescribed below.

According to the first exemplary embodiment, when the calibration isperformed, the CPU 103 requests a user to determine whether to performthe other calibration.

However, a long processing time is required when two types ofcalibrations are performed constantly and continuously as a result ofthe request. In addition, when the printer usage status that is variabledepending on each user is taken into consideration, a sufficientcorrection result may be obtained in some cases even when only one ofthe two types of calibrations is performed. For example, if a userfrequently performs black monochrome printing, the K color (i.e., asingle color) is mainly used. Therefore, the execution frequency of thesingle-color calibration can be increased compared to that of themulti-color calibration.

Considering the above-described situation, the image processing systemaccording to the present exemplary embodiment compares the number ofcolor printed sheets with the number of monochrome printed sheets andswitches a UI screen according to a monochrome printing output ratio, asdescribed below.

FIG. 13 illustrates a processing procedure according to the presentexemplary embodiment. The CPU 103 provided in the controller 102performs the following processing illustrated in FIG. 13. The storagedevice 121 stores the obtained data. Further, the display device 118displays a UI screen including an instruction message to a user, and theinput device 120 receives an instruction from the user.

In step S1301, the CPU 103 starts the multi-color calibration. Morespecifically, the CPU 103 starts the multi-color calibration if a userpresses the button 603 displayed by the display device 118 via the inputdevice 120.

Next, in step S1302, the CPU 103 analyzes the number of printed sheetswith reference to a “number of monochrome printed sheets” counter 1303,a “number of color printed sheets” counter 1304, and a threshold value1305. The “number of monochrome printed sheets” counter 1303 indicatesthe number of monochrome printed sheets having been output afterperforming the last calibration (i.e., the single-color calibration orthe multi-color calibration). The “number of monochrome printed sheets”counter 1303 increments its count value each time when a monochromeprinting is performed in an ordinary job. The “number of color printedsheets” counter 1304 indicates the number of color printed sheets havingbeen output after performing the last calibration. The “number of colorprinted sheets” counter 1304 increments its count value each time when acolor printing is performed in an ordinary job.

As an analyzing method, the following formula (1) is used to calculate aratio R with reference to count values of the “number of monochromeprinted sheets” counter 1303 and the “number of color printed sheets”counter 1304.

$\begin{matrix}{\left\lbrack {{Formula}\mspace{14mu} 1} \right\rbrack\mspace{610mu}} & \; \\{R = \frac{CNTm}{\left( {{CNTm} + {CNTc}} \right)}} & (1)\end{matrix}$In formula (1), CNTm represents the number of monochrome printed sheets,and CNTc represents the number of color printed sheets.

The threshold value 1305 is compared with the ratio R. If the ratio R isgreater than the threshold value, the CPU 103 determines that thecurrent print operation is mainly performed for the monochrome printing.

Next, in step S1306, the CPU 103 determines whether the monochromeprinting output ratio is equal to or greater than a threshold value withreference to the ratio R and the threshold value 1305.

If it is determined that the monochrome printing output ratio is lessthan the threshold value (NO in step S1306), then in step S1307, the CPU103 causes the display device 118 to display a UI screen forrecommending a user to perform the multi-color calibration. When themonochrome printing output ratio is less than the threshold value, theratio of color printing is relatively high. Therefore, performing themulti-color calibration is useful to obtain high correction accuracy.FIG. 14A illustrates an example of a UI screen 1401 that can bedisplayed by the display device 118. The UI screen 1401 includes twobuttons 1403 and 1404 that are similar to the buttons 803 and 804illustrated in FIG. 8, and therefore redundant description thereof willbe avoided. The UI screen 1401 includes a display field 1402 in which amessage for recommending to perform the multi-color calibration andrequesting a user to determine whether to perform the multi-colorcalibration is displayed. The UI screen 1401 includes a display field1405 in which the number of color printed sheets and the number ofmonochrome printed sheets having been output after the last calibrationare indicated, thus a user can check the number of output sheets in thedisplay field 1405 as a criterion of determination.

If it is determined that the monochrome printing output ratio is equalto or greater than the threshold value (YES in step S1306), then in stepS1308, the CPU 103 causes the display device 118 to display a UI screenthat does not recommend a user to perform the multi-color calibration.When the monochrome printing output ratio is equal to or greater thanthe threshold value, the ratio of monochrome printing is relativelyhigh. Therefore, even if the multi-color calibration is performed, thevalidity is low. FIG. 14B illustrates an example of a UI screen 1406that can be displayed by the display device 118. The UI screen 1406includes two buttons 1408 and 1409 that are similar to the buttons 803and 804 illustrated in FIG. 8, and therefore redundant descriptionthereof will be avoided. The UI screen 1406 includes a display field1407 in which a message for not recommending to perform the multi-colorcalibration and requesting a user to determine whether to perform themulti-color calibration without change is displayed. The UI screen 1406includes a display field 1410 in which the number of color printedsheets and the number of monochrome printed sheets having been outputafter the last calibration are indicated, thus a user can check thenumber of output sheets in the display field 1410 as a criterion ofdetermination.

In step S1309, the CPU 103 determines whether to perform the multi-colorcalibration. More specifically, the CPU 103 determines whether theselected button is the “YES” button 1403 (or 1408) or the “NO” button1404 (or 1409).

If it is determined that the multi-color calibration is performed (YESin step S1309), then in step S1310, the CPU 103 performs the multi-colorcalibration. The processing to be performed in step S1310 is similar tothe processing performed in steps S401 to S411, and therefore redundantdescription thereof will be avoided.

If it is determined that the multi-color calibration is not performed(NO in step S1309), then in step S1311, the CPU 103 performs thesingle-color calibration. The processing to be performed in step S1311is similar to the processing performed in steps S301 to S315, andtherefore redundant description thereof will be avoided.

Next, in step S1312, the CPU 103 initializes the “number of monochromeprinted sheets” counter 1303 and the “number of color printed sheets”counter 1304, and then terminates the processing of the flowchartillustrated in FIG. 13. After the counter is initialized, the number ofoutput sheets becomes zero.

According to the present exemplary embodiment, the threshold value 1305is a fixed value. However, a user may set the threshold value 1305 viathe display device 118 and the input device 120.

Further, according to the present exemplary embodiment, although the CPU103 performs the single-color calibration when the multi-colorcalibration is not performed, the CPU 103 can terminate the processingof the flowchart illustrated in FIG. 13 without performing thesingle-color calibration.

According to the above-described exemplary embodiment, the system canrequest a user to determine whether to perform a single-colorcalibration before starting a multi-color calibration among two types ofthe calibrations. Thus, the system can prevent the correction accuracyin the multi-color calibration from deteriorating due to non-executionof the single-color calibration.

Further, the display of whether to recommend the multi-color calibrationin the display unit can be switched according to the monochrome printingoutput ratio, so that a user can easily determine whether to perform themulti-color calibration.

Further, displaying the number of color printed sheets and the number ofmonochrome printed sheets is useful to enable a user to easily determinewhether to perform the multi-color calibration.

Further, the present invention is applicable to an inkjet printer or athermal printer although the above-described exemplary embodiments aredescribed based on an electrophotographic apparatus. The scope of thepresent invention is not limited to a specific printer type. Further,the toner is an example of the recording agent usable inelectrophotographic printing. However, any other appropriate recordingagent (e.g., ink) can be used in the printing. The scope of the presentinvention is not limited to a specific recording agent type.

Embodiments of the present invention can also be realized by a computerof a system or apparatus that reads out and executes computer executableinstructions recorded on a storage medium (e.g., non-transitorycomputer-readable storage medium) to perform the functions of one ormore of the above-described embodiments of the present invention, and bya method performed by the computer of the system or apparatus by, forexample, reading out and executing the computer executable instructionsfrom the storage medium to perform the functions of one or more of theabove-described embodiments. The computer may comprise one or more of acentral processing unit (CPU), micro processing unit (MPU), or othercircuitry, and may include a network of separate computers or separatecomputer processors. The computer executable instructions may beprovided to the computer, for example, from a network or the storagemedium. The storage medium may include, for example, one or more of ahard disk, a random-access memory (RAM), a read only memory (ROM), astorage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)(trademark)), a flash memory device, a memory card, and the like.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all modifications, equivalent structures, and functions.

What is claimed is:
 1. An image processing apparatus comprising: one ormore memories storing instructions; and one or more processors whichexecute the instructions: the one or more processors perform thefollowing operations: first operation (i): obtaining color measurementvalues of a plurality of images including at least first color imagesand second color images and generating first correction data, the firstcolor images being formed using a first color recording material withoutusing a color recording material other than the first color recordingmaterial, wherein the first color images are formed with differentamounts of the first color recording material, and the second colorimages being formed using a second color recording material which isdifferent from the first color recording material without using a colorrecording material other than the second color recording material,wherein the second color images are formed with different amounts of thesecond color recording material, the plurality of images not including acolor image formed by superposition of a plurality of color recordingmaterials; and second operation (ii): obtaining color measurement valuesof a plurality of multi-color images and generating second correctiondata, at least two of the plurality of multi-color images being formedusing a plurality of color recording materials, and at least one of theplurality of multi-color images being a chromatic color image, whereinbased on a user's first instruction, the first operation (i) isperformed without the second operation (ii) being performed, and, basedon a user's second instruction, the first operation (i) and the secondoperation (ii) are performed.
 2. The image processing apparatusaccording to claim 1, wherein, based on a user's third instruction, thesecond operation (ii) is performed without the first operation (i) beingperformed.
 3. The image processing apparatus according to claim 1,wherein based on the user's second instruction, after the firstoperation (i) has been performed, the second operation (ii) is performedwithout a further instruction being received from a user.
 4. The imageprocessing apparatus according to claim 1, further comprising a displaydevice, wherein the user's first instruction and the user's secondinstruction are received via a screen displayed by the display device.5. The image processing apparatus according to claim 1, wherein thefirst color recording material is a cyan color recording material, andthe second color recording material is a magenta color recordingmaterial.
 6. The image processing apparatus according to claim 1,wherein the plurality of color recording materials is at least two of acyan color recording material, a magenta color recording material, and ayellow color recording material.
 7. The image processing apparatusaccording to claim 1, wherein the at least one of the plurality ofmulti-color images is an ge formed by superposition of toners of aplurality of colors.
 8. The image processing apparatus according toclaim 1, wherein the second operation (ii) is performed using thecorrection data generated by the first operation (i).
 9. An imageprocessing method comprising: performing color measurements of aplurality of images including at least first color images and secondcolor images and generating monochromatic correction data based on auser's first instruction, the first color images being formed using afirst color recording material without using a color recording materialother than the first color recording material, wherein the first colorimages are formed with different amounts of the first color recordingmaterial and the second color images being formed using a second colorrecording material which is different from the first color recordingmaterial without using a color recording material other than the secondcolor recording material, wherein the second color images are formedwith different amounts of the second color recording material, theplurality of images not including a color image formed by superpositionof a plurality of color recording materials; and performing the colormeasurements of the plurality of images including at least the firstcolor images and the second color images, generating the monochromaticcorrection data and performing color measurements of a plurality ofmulti-color images and generating multi-color correction data based on auser's second instruction, at least two of the plurality of multi-colorimages being formed using a plurality of color recording materials, atleast one multi-color image of the plurality of multi-color images beinga chromatic color image.
 10. The method according to claim 9, furthercomprising performing the color measurements of the plurality of imagesincluding at least the first color images and the second color images,generating the monochromatic correction data and performing colormeasurements of a plurality of multi-color images and generatingmulti-color correction data based on a user's third instruction.
 11. Themethod according to claim 9, wherein based on the user's secondinstruction, after the performing of the color measurements of theplurality of images including at least first color images and secondcolor images and the generating of the monochromatic correction databased on the user's first instruction, the performing of the colormeasurements of the plurality of images including at least the firstcolor images and the second color images, the generating of themonochromatic correction data and the performing of the colormeasurements of the plurality of multi-color images and the generatingmulti-color correction data based on the user's second instruction areperformed without receiving a further instruction from a user.
 12. Themethod according to claim 9, further comprising receiving the user'sfirst instruction and the user's second instruction via a screendisplayed by a display device.
 13. The method according to claim 9,wherein the first color recording material is a cyan color recordingmaterial, and the second color recording material is a magenta colorrecording material.
 14. The method according to claim 9, wherein theplurality of color recording materials is at least two of a cyan colorrecording material, a magenta color recording material, and a yellowcolor recording material.
 15. The method according to claim 9, whereinthe at least two of the plurality of multi-color images are imagesformed by superposition of toners of a plurality of colors.
 16. Themethod according to claim 9, wherein the performing of the colormeasurements of the plurality of images including at least the firstcolor images and the second color images, the generating of themonochromatic correction data and the performing of the colormeasurements of the plurality of multi-color images and the generatingmulti-color correction data based on the user's second instruction areperformed using the monochromatic correction data generated by theperforming of the color measurements of the plurality of imagesincluding at least first color images and second color images and thegenerating of the monochromatic correction data based on the user'sfirst instruction.
 17. A non-transitory computer-readable storage mediumstoring a program that causes a computer to execute an image processingmethod, the image processing method comprising: performing colormeasurements of a plurality of images including at least first colorimages and second color images and generating monochromatic correctiondata based on a user's first instruction, the first color images beingformed using a first color recording material without using a colorrecording material other than the first color recording material,wherein the first color images are formed with different amounts of thefirst color recording material and the second color images being formedusing a second color recording material which is different from thefirst color recording material without using a color recording materialother than the second color recording material, wherein the second colorimages are formed with different amounts of the second color recordingmaterial, the plurality of images not including a color image formed bysuperposition of a plurality of color recording materials; andperforming the color measurements of the plurality of images includingat least the first color images and the second color images, generatingthe monochromatic correction data and performing color measurements of aplurality of multi-color images and generating multi-color correctiondata based on a user's second instruction, at least two of the pluralityof multi-color images being formed using a plurality of color recordingmaterials, at least one multi-color image of the plurality ofmulti-color images being a chromatic color image.
 18. The imageprocessing apparatus according to claim 1, wherein the one or moreprocessors further cause the image processing apparatus to receive theuser's second instruction but not receive the user's first instructionuntil a predetermined time elapses from a time when the image processingapparatus is turned on.
 19. The image processing apparatus according toclaim 1, wherein the one or more processors further cause the imageprocessing apparatus to receive the user's second instruction but notreceive the user's first instruction in a case where the firstprocessing unit and the second processing unit had not operated for apredetermined time.
 20. The image processing apparatus according toclaim 1, wherein the one or more processors further cause the imageprocessing apparatus to receive the user's second instruction but notreceive the user's first instruction in a case where the first operation(i) and the second operation (ii) had not been performed until apredetermined number of sheets have been used in printing.
 21. The imageprocessing apparatus according to claim 1, wherein the at least one ofthe plurality of multi-color images is a red color image formed bysuperposition of recording materials of a plurality of colors.
 22. Theimage processing apparatus according to claim 1, wherein the at leastone of the plurality of multi-color images is a green color image formedby superposition of recording materials of a plurality of colors. 23.The image processing apparatus according to claim 1, wherein the atleast one of the plurality of multi-color images is a blue color imageformed by superposition of recording materials of a plurality of colors.24. The image processing apparatus according to claim 1, wherein thefirst color images are cyan color images, the second color images aremagenta color images, and at least one of the plurality of multi-colorimages is a blue color image formed by superposition of a cyan colorrecording material and a magenta color recording material.
 25. An imageprocessing apparatus comprising: one or more memories storinginstructions; and one or more processors which execute the instructions:the one or more processors perform the following operations: firstoperation (i): obtaining color measurement values of a plurality ofimages including at least first color images and second color images andgenerating first correction data, the first color images being formedusing a first color recording material without using a color recordingmaterial other than the first color recording material, wherein thefirst color images are formed with different amounts of the first colorrecording material, and the second color images being formed using asecond color recording material which is different from the first colorrecording material without using a color recording material other thanthe second color recording material, wherein the second color images areformed with different amounts of the second color recording material,the plurality of images not including a color image formed bysuperposition of a plurality of color recording materials; and secondoperation (ii): obtaining color measurement values of a plurality ofmulti-color images and generating second correction data, at least twoof the plurality of multi-color images being formed using a plurality ofcolor recording materials, and at least one of the plurality ofmulti-color images being a chromatic color image, wherein, based on anexecution instruction, the first operation (i) is performed without thesecond operation (ii) being performed and, based on an executioninstruction, the first operation (i) and the second operation (ii) areperformed.
 26. The image processing apparatus according to claim 25,wherein the execution instruction based on which the first operation (i)is performed without the second operation (ii) being performed isdifferent from the execution instruction based on which the firstoperation (i) and the second operation (ii) are performed.
 27. The imageprocessing apparatus according to claim 1, wherein the first correctiondata is data for correcting monochromatic gradation characteristics. 28.The image processing apparatus according to claim 1, wherein the secondcorrection data is data for correcting multi-color reproductioncharacteristics formed by a combination of a plurality of toners ofdifferent colors.